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Pristis pristis
Pristis pristis (''Common sawfish, largetooth sawfish)' Kingdom: '''Animalia Phylum: Chordata Class: Chondrichthyes Order: Pristiformes Family: Pristidae Genus: Pristis Species: Pristis pristis Environment: milieu, climate zone, depth range, distribution range: Marine; freshwater; brackish; demersal; oceanodromous; depth range 25 - ? m. Subtropical; 35°N - 40°S, 120°W - 160°E. Distribution: Circumglobally in tropical and subtropical waters, entering estuaries and littoral lagoons and ascending river courses. Western Atlantic: Florida and Louisiana, USA to Brazil; eastern Atlantic: Portugal to Angola, including the western Mediterranean Sea (no report since the 19th century); western Pacific: northern Australia, from western Australia to Queensland; eastern Pacific: Gulf of California to Ecuador. In freshwater it can be found in rivers of West Africa, Ogowe River and the Congo River estuary. Size, weight, age: Max. length: 7.50 m, common length: 2.50 m; age: 30 years Short description: The largetooth sawfish possibly reaches up to 7.5 m (25 ft) in total length, but the largest confirmed was a West African individual that was 7 m (23 ft) long. An individual caught in 1951 at Galveston, Texas, which was documented on film but not measured, has been estimated to be of similar size. Today most individuals are far smaller and a typical length is 2–2.5 m (6.6–8.2 ft). Large individuals may weigh as much as 500–600 kg (1,102–1,323 lb), or possibly even more. The largetooth sawfish is easily recognized by the forward position of the dorsal fin with its leading edge placed clearly in front of the leading edge of the pelvic fins (when the sawfish is seen from above or the side), the relatively long pectoral fins with angular tips, and the presence of a small lower tail lobe. In all other sawfish species the leading edge of their dorsal fin is placed at, or behind, the leading edge of the pelvic fins, and all other Pristis sawfish species have shorter pectoral fins with less pointed tips and lack a distinct lower tail lobe (very small or none). The rostrum ("saw") of the largetooth sawfish has a width that is 15–25% of its length, which is relatively wide compared to the other sawfish species, and there are 14–24 equally separated teeth on each side of it. On average, females have shorter rostrums with fewer teeth than males. The proportional rostrum length also varies with age, with average being around 27% of the total length of the fish, but can be as high as 30% in juveniles and as low as 20–22% in adults. Its upperparts are generally grey to yellowish-brown, often with a clear yellow tinge to the fins. Individuals in freshwater may have a reddish colour caused by blood suffusion below the skin. The underside is greyish or white. Biology: A euryhaline species. Inhabits inshore coastal waters to moderate depth, also around off lying islands. Found also in estuaries, lagoons, river mouths, and even freshwater. Feeds on fishes and bottom-living animals. Ovoviviparous. Apparently can reproduce in freshwater. Freshwater populations occur to about 750 km up Amazon River; populations in Lake Nicaragua may be non-migratory. Reaches sexual maturity at 8-10 years and females have litters of approximately 1-13 pups. Young spend much of their early life in rivers up to 400 km from the sea. Life cycle and mating behavior: Sexual maturity is reached at a length of about 2.8–3 m (9.2–9.8 ft) when 7–10 years old. Breeding is seasonal in this ovoviviparous species, but the exact timing appears to vary depending on the region. The adult females can breed once every 1–2 years, the gestation period is about five months, and there are indications that mothers return to the region where they were born to give birth to their own young. There are 1–13 (average c. 7) young in each litter, which are 72–90 cm (28–35 in) long at birth. They are likely typically born in salt or brackish water near river mouths, but move into freshwater where the young spend the first 3–5 years of their life, sometimes as much as 400 km (250 mi) upriver. In the Amazon basin the largetooth sawfish has been reported even further upstream, and this mostly involves young individuals that are up to 2 m (6.6 ft) long. Occasionally, young individuals become isolated in freshwater pools during floods and may live there for years. The potential lifespan of the largetooth sawfish is unknown, but four estimates suggested 30 years, 35 years, 44 years, and 80 years. The largetooth sawfish is a predator that feeds on fish, molluscs and crustaceans. The "saw" can be used both to stir up the bottom to find prey and to slash at groups of fish. Sawfish are docile and harmless to humans, except when captured where they can inflict serious injuries when defending themselves with the "saw". Main reference: Stehmann, M., 1990. Pristidae. p. 51-54. In J.C. Quero, J.C. Hureau, C. Karrer, A. Post and L. Saldanha (eds.) Check-list of the fishes of the eastern tropical Atlantic (CLOFETA). JNICT, Lisbon; SEI, Paris; and UNESCO, Paris. Vol. 1. IUCN Red List Status: CRITICALLY ENDANGERED (''CR)' '''CITES: Appendix I: International trade banned CMS: Appendix I & II: Endangered migratory species conserved through agreements Threat to humans: Harmless Human uses: Fisheries: minor commercial. Category:Pristidae, Sawfishes